Optibay SSD drive speed question

timc43 · Sep 19, 2012

Hi there,

I have a 2011 unibody MacBook Pro, 2.2 GHz Intel Core i7 with a 250GB SSD drive installed. I run a lot of full HD live video with multiple layers and have found the internal SSD really great in handling this. However I can only just fit one show on my machine and I'm about to go on tour with 2 different shows. So rather than constantly copying over from an external drive, I am looking for a solution to get it all in one place.

So I am considering getting an Optibay and adding another similar sized SSD drive in there.

- Will I still achieve the same data transfer speeds or is it a waste to put an SSD drive in there?
- Would i be better off just getting a bigger SSD and switching it out for the current one?
- Or should I consider going for a thunderbolt SSD?

Many thanks in advance.

McYukon · Sep 19, 2012

#1 To find that out open the System Profiler and look under the Serial-ATA section.
Link Speed is the main HDD bays link speed to the bus, whereas the Negotiated Link Speed is what the optical bay is linked with. I keep the SSD in the main bay, as my optical drive is only 1.5GB/s whereas my main HDD bay is 3GB/s.

#2 IMO, yes

#3 Another option, although you have to decide if you want something separate to lug around

timc43 · Sep 20, 2012

McYukon said:
#1 To find that out open the System Profiler and look under the Serial-ATA section.
Link Speed is the main HDD bays link speed to the bus, whereas the Negotiated Link Speed is what the optical bay is linked with. I keep the SSD in the main bay, as my optical drive is only 1.5GB/s whereas my main HDD bay is 3GB/s.

#2 IMO, yes

#3 Another option, although you have to decide if you want something separate to lug around

ok thanks for the info and you reply.

so this is what my system profiler says:

Intel 6 Series Chipset:

Vendor: Intel
Product: 6 Series Chipset
Link Speed: 6 Gigabit
Negotiated Link Speed: 3 Gigabit
Description: AHCI Version 1.30 Supported

APPLE SSD TS256C:

Capacity: 251 GB (251,000,193,024 bytes)
Model: APPLE SSD TS256C
Revision: CJAA0201
Serial Number: 31BS10GGTLNZ
Native Command Queuing: No
Removable Media: No
Detachable Drive: No
BSD Name: disk0
Medium Type: Solid State
TRIM Support: Yes
Partition Map Type: GPT (GUID Partition Table)
S.M.A.R.T. status: Verified
Volumes:
Capacity: 209.7 MB (209,715,200 bytes)
Writable: Yes
BSD Name: disk0s1
Macintosh HD:
Capacity: 250.66 GB (250,656,219,136 bytes)
Available: 8.82 GB (8,824,107,008 bytes)
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s2
Mount Point: /

And then:

Intel 6 Series Chipset:

Vendor: Intel
Product: 6 Series Chipset
Link Speed: 6 Gigabit
Negotiated Link Speed: 1.5 Gigabit
Description: AHCI Version 1.30 Supported

MATSHITADVD-R UJ-898:

Model: MATSHITADVD-R UJ-898
Revision: HE13
Serial Number: UL21 230A6V
Native Command Queuing: No
Detachable Drive: No
Power Off: Yes
Async Notification: No

So does this mean I will get a speed of 3 GB or 1.5 GB if I put a drive in the optibay?

Many thanks

McYukon · Sep 20, 2012

Alright, the main HDD bay has a link speed of 6 GB/s negotiated to 3 GB/s for some reason. Probably because of the SDD you have in there doesn't support 6 GB/s as it might be one of the older SSD's that operate on SATA II

SATA revision I (SATA 1.5 Gbit/s)
SATA revision II (SATA 3 Gbit/s)
SATA revision III (SATA 6 Gbit/s)

Now the second one is the the DVD drive (MATSHITADVD), it is negotiated to 1.5 GB/s by the system (Not changeable, according to various people smarter than me)

So you will get a link speed of 1.5 GB/s if you put a SSD into the optibay.

Stretch · Sep 21, 2012

timc43 said:
ok thanks for the info and you reply.

so this is what my system profiler says:

Intel 6 Series Chipset:

Vendor: Intel
Product: 6 Series Chipset
Link Speed: 6 Gigabit
Negotiated Link Speed: 3 Gigabit
Description: AHCI Version 1.30 Supported

APPLE SSD TS256C:

Capacity: 251 GB (251,000,193,024 bytes)
Model: APPLE SSD TS256C
Revision: CJAA0201
Serial Number: 31BS10GGTLNZ
Native Command Queuing: No
Removable Media: No
Detachable Drive: No
BSD Name: disk0
Medium Type: Solid State
TRIM Support: Yes
Partition Map Type: GPT (GUID Partition Table)
S.M.A.R.T. status: Verified
Volumes:
Capacity: 209.7 MB (209,715,200 bytes)
Writable: Yes
BSD Name: disk0s1
Macintosh HD:
Capacity: 250.66 GB (250,656,219,136 bytes)
Available: 8.82 GB (8,824,107,008 bytes)
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s2
Mount Point: /

And then:

Intel 6 Series Chipset:

Vendor: Intel
Product: 6 Series Chipset
Link Speed: 6 Gigabit
Negotiated Link Speed: 1.5 Gigabit
Description: AHCI Version 1.30 Supported

MATSHITADVD-R UJ-898:

Model: MATSHITADVD-R UJ-898
Revision: HE13
Serial Number: UL21 230A6V
Native Command Queuing: No
Detachable Drive: No
Power Off: Yes
Async Notification: No

So does this mean I will get a speed of 3 GB or 1.5 GB if I put a drive in the optibay?

Many thanks

McYukon said:
Alright, the main HDD bay has a link speed of 6 GB/s negotiated to 3 GB/s for some reason. Probably because of the SDD you have in there doesn't support 6 GB/s as it might be one of the older SSD's that operate on SATA II

Now the second one is the the DVD drive (MATSHITADVD), it is negotiated to 1.5 GB/s by the system (Not changeable, according to various people smarter than me)

So you will get a link speed of 1.5 GB/s if you put a SSD into the optibay.

No, the SATA slots are both SATA III, or 6GB/s. They are negotiated at the listed speeds because of what is connected to them. I'm guessing the current devices are a SATA II SSD and the factory optical drive? If you replace one of those, or both for that matter with a SATA III device, the negotiated speed will change to 6GB/s.

Lifeisabeach · Sep 21, 2012

Stretch said:
No, the SATA slots are both SATA III, or 6GB/s. They are negotiated at the listed speeds because of what is connected to them. I'm guessing the current devices are a SATA II SSD and the factory optical drive? If you replace one of those, or both for that matter with a SATA III device, the negotiated speed will change to 6GB/s.

Agreed here. I have a mid-2010 iMac with the Intel 5 Series chipset that supports 3 Gigabit speeds (i.e. it's older and slower). I replaced my optical drive with an OWC SSD and that, as well as my internal HDD, both are negotiating at the full 3 Gigabits.

Back to the OP: It looks like you should be in good shape to swap out the optical drive for an SSD... assuming you don't need the optical drive anyway. But what should be pointed out also (EDIT: actually Stretch already did... LOL!) is that your existing SSD is apparently not meeting the full potential of your 6 Gb SATA connection. Whatever you decide to do, you should consider getting an SSD that is 6 Gb capable for the maximum performance. OWC has some that will fit the bill here, and their Mac support is top notch.

timc43 · Sep 21, 2012

Stretch said:
No, the SATA slots are both SATA III, or 6GB/s. They are negotiated at the listed speeds because of what is connected to them. I'm guessing the current devices are a SATA II SSD and the factory optical drive? If you replace one of those, or both for that matter with a SATA III device, the negotiated speed will change to 6GB/s.

Yes, this is correct. So if I put a 6GB/s drive in the optical bay, it will run at full speed?

timc43 · Sep 21, 2012

Ok great, thanks for clearing that all up everyone.

many thanks
tim

microsnook · Sep 21, 2012

In my 2011 MBP both slots are 6GB/s and I have dual SSDs set to RAID. You should be fine.

I would get another and replace the optical drive or regular HDD.

anynamewilldo · Sep 22, 2012

FWIW, I had a mid-2012 13", with an SSD in the main bay and the stock HD in the optical bay. I get:

MAIN BAY: OWC Mercury EXTREME Pro 6G SSD
Vendor: Intel
Product: 7 Series Chipset
Link Speed: 6 Gigabit
Negotiated Link Speed: 6 Gigabit
Description: AHCI Version 1.30 Supported

OPTICAL BAY: TOSHIBA MK7559GSXF
Vendor: Intel
Product: 7 Series Chipset
Link Speed: 6 Gigabit
Negotiated Link Speed: 3 Gigabit
Description: AHCI Version 1.30 Supported

timc43 · Oct 3, 2012

Ok, so thanks to everyone for their input and help.

I went for the OWC Mercury Extreme Pro 6G SSD with the OWC enclosure. All went just fine with one laptop. Installed and formated and running perfectly.

However, with the second laptop, things weren't so smooth. followed the same install steps, and all seemed fine until I got the formatting stage and it is giving me a "POSIX input/output error" and saying unable to erase disk.

Any ideas? have I damaged something installing it?

Lifeisabeach · Oct 3, 2012

timc43 said:
However, with the second laptop, things weren't so smooth. followed the same install steps, and all seemed fine until I got the formatting stage and it is giving me a "POSIX input/output error" and saying unable to erase disk.

Any ideas? have I damaged something installing it?

Read over the guides linked below to see if the tips there will get you up. If not, I would just plan on returning the drive for a replacement. I'm highly skeptical that this is a problem on your part.

Partitioning USB hard drives that fail in Disk Utility with 'POSIX' error | MacFixIt - CNET Reviews

Partition falied Input/Output Error

timc43 · Oct 3, 2012

lifeisabeach said:
Read over the guides linked below to see if the tips there will get you up. If not, I would just plan on returning the drive for a replacement. I'm highly skeptical that this is a problem on your part.

Partitioning USB hard drives that fail in Disk Utility with 'POSIX' error | MacFixIt - CNET Reviews

Partition falied Input/Output Error

Ok - so I got onto OWC tech chat (this was the main reason I spent the extra cash on a OWC drive) here is a bit of our conversation:

[9:32:01 AM] On the MBP 8,2 series 6G drives are not recommend for use in the Data Doubler in the optical bay
Tim: [9:32:24 AM] right ok - why is that?
OWC Matt: [9:33:16 AM] The SATA controller used in the optical bay has issues with 6G devices
Tim: [9:34:48 AM] i did a lot of research into this before I bought these drives and never came across this being a potential issue
OWC Matt: [9:35:35 AM] It has been an issue on the 15" MBP for a bit
[9:35:48 AM] The drive will work fine in the main drive bay
Tim: [9:36:23 AM] ok - so i should switch it round with the apple ssd into the optibay>
[9:36:36 AM] that is a 3G drive
OWC Matt: [9:36:55 AM] Yes sir that will work fine like that

And this solved my problem! Now works just fine. However it doesn't explain why one identical machine was fine, while the other had issues. The only difference is one is running 10.6.7 and the other is 10.6.8. And its the 10.6.7 that works. And it also goes against others experience in this thread who are successfully running 2 6G drives.

go figure?

anynamewilldo · Oct 3, 2012

timc43 said:
And this solved my problem! Now works just fine. However it doesn't explain why one identical machine was fine, while the other had issues. The only difference is one is running 10.6.7 and the other is 10.6.8. And its the 10.6.7 that works. And it also goes against others experience in this thread who are successfully running 2 6G drives.

You have to understand the nature of manufacturing. Here is what "has issues" means:

a). Manufacturers source different parts from different vendors.
b). Specs for parts include a tolerance for different things.
c). Different parts may perform differently under the same conditions.
d). Identical model machines may have the same part from different vendors.

The result is that machine A and machine B may perform differently when purposed in a way that is outside of a manufacturer's explicit stated support, even when machine A and machine B are the same model.

So, someone buying machine ABC may "get lucky" and get the parts that work with the optical drive yanked and replaced with a 6G SSD. Some people buying the same machine "get unlucky" and get the lame parts that will not work (reliably) in this configuration. There is no good way of telling, in advance, what you have. In any event, Apple doesn't advertise that using the machine in this configuration is supported, so you're not going to have much room to go back to them and complain (not that you would - I'm just talking in general).

As for your research - I DID come across the bit about 6G devices in some optical bays - it's right on OWC's website. For this reason, when I installed my SSD (Same as yours), I put it in the HD bay and put the stock HD in the optical bay, EVEN THOUGH my machine is not of a model that is "known to have issues" when putting a 6G drive in the optical bay. I just didn't want to risk having any issues with it.